"Other" keeps coming back
I have an iPhone 6 and recently every other time I plug my it in to sync with my iTunes it says my entire phone is full with the "Other" category (like 39gigs). When I try to resync it says my phone is now over capacity. The only way to resolve this is to do a restore, but it keeps coming back. Anyone know what I should do?
iPhone 6, iOS 9.1